myView.removeFromSuperview() don't delete my line on myView, why?

Question

I have made a greenView:

static func createRectView(
    x: Float,
    y: Float,
    width: Float,
    height: Float,
    color: UIColor,
    transparency: Float
) -> UIView {
    let viewRectFrame = CGRect(
        x: CGFloat(x),
        y: CGFloat(y),
        width: CGFloat(width),
        height: CGFloat(height)
    )
    let retView = UIView(frame:viewRectFrame)
    retView.backgroundColor = color
    retView.alpha = CGFloat(transparency)
    return retView
}
let greenView: UIView = createRectView(
    x: 50,
    y: 110,
    width: 150,
    height: 100,
    color: .green,
    transparency: 1
)
view.addSubview(greenView)

I have drawn a line on greenView:

func getPath() -> UIBezierPath {
    let path = UIBezierPath()
    path.move(to: CGPoint(x: 0, y: 0))
    path.addLine(to: pointDef5)
    return path
}

func createLine(on view: UIView) {
    let shapeLayer = CAShapeLayer()
    view.layer.addSublayer(shapeLayer)
    shapeLayer.strokeColor = UIColor.black.cgColor
    shapeLayer.lineWidth = 5
    shapeLayer.fillColor = nil 
    shapeLayer.path = getPath().cgPath
}

createLine(on: greenView)

I have removed and added greenView:

greenView.removeFromSuperview()
view.addSubview(greenView)

I see my old line on absurd greenView! How delete my line from my greenView?

greenView + line = forever? I don't know how delete a line

enter image description here

Ely · Answer 1 · 2023-03-05T15:17:45.343

1

In your code, greenView is created once and then added to self.view. Removing and re-adding this view does not change the view.

The line in your code is added as a sublayer on greenView. To remove the line, you must remove the sublayer.

For example, try this:

greenView.layer.sublayers?.removeAll()

edited Mar 05 '23 at 15:17

answered Mar 05 '23 at 13:39

Ely

8,259
1
54
67

view.layer?.sublayers?.removeAll() it doesn't work - error – Swift Lilu Mar 05 '23 at 13:52
@SwiftLilu give a name to your view setting it’s layer name property. This way if you need to delete it you can search which subview has its layer name and remove it. Check this [post](https://stackoverflow.com/a/62093932/2303865) – Leo Dabus Mar 05 '23 at 13:55
@Leo please write in more detail :-( I want to delete stupid line from my greenView! – Swift Lilu Mar 05 '23 at 14:02
The link above does exactly what you need with a gradient layer. Just do the same with your CAShapeLayer – Leo Dabus Mar 05 '23 at 14:07
@LEO can you write CODE please – Swift Lilu Mar 05 '23 at 14:11
@Ely ======> view.greenView.sublayers.removeAll() ====> Value of type 'UIView' has no member 'greenView' ====> EROR – Swift Lilu Mar 05 '23 at 14:16
@SwiftLilu I corrected my code. – Ely Mar 05 '23 at 15:19
1

@Ely it worked! SUPER!!! Ely - I love you!!! Thank you! – Swift Lilu Mar 05 '23 at 16:12

myView.removeFromSuperview() don't delete my line on myView, why?

1 Answers1